Chris Carpenter might be about to make one of the latest season debuts by a player who'll appear on a playoff roster, but he has nothing on Steve Torrealba.

Chris Carpenter will make his 2012 debut for the Cardinals tomorrow afternoon at Wrigley Field, which means he’ll have time for only two starts before the playoffs. Carpenter last pitched in the seventh game of the 2011 World Series, so he’s essentially skipped the low-stakes section of the season and skipped straight to the exciting parts. (Thanks, thoracic outlet syndrome!)

Every September 1, teams across the league call up a myriad of players: some top prospects, some fringe specialists, and the occasional organizational soldier. They all have different purposes leading to one main goal: improving the big league team over the season’s final five weeks. This year looked to be no different approaching September, then began a wave of arguments against the practices of September roster expansion. Historians will identify Joel Sherman of the New York Postas the first writer to shoot. Sherman’s article offered strong language, supporting quotes from those within the industry, and, in a clear act of aggression, a Three Stooges reference. Sherman concludes like so:

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Examining the methods by which teams can expand their roster options in October.

Baseball’s postseason rosters will lock into place at the stroke of midnight tonight, when the roster expansion period begins. Only the players on each team’s 25-man roster at that time will be eligible to play in the postseason. That rule was devised to prevent playoff-bound teams from loading up on rentals during the final two weeks of the season (as the rest of the league is eliminated from contention), as well as calling up their top prospects just for the postseason. However, there is a way to circumvent that rule and essentially add a 26th, 27th, and occasionally a 28th man to the playoff roster pool, and it involves the disabled list.

Simply put, a team can substitute another player from the 40-man roster for any player on the team’s major-league 60-day disabled list after August 31. The catch, and it is a minor one, is that only pitchers can replace pitchers and only positional players can replace positional players. This exception came to prominence in 2002, when the Angels used their exception from Steve Green on Francisco Rodriguez, but it has been used throughout the last few seasons, by the Rays in particular.

In Part I, I looked at how the position players on the Giants’ World Series roster came together. Now, we’ll track and analyze how the club’s pitching staff wound up in San Francisco.

Please know that the reason Barry Zito, the Giants southpaw with the most lucrative contract, (a seven-year, $126 million deal) is not on this list because he was indeed left off the post-season roster. Past that, you’ll see a smartly designed pitching corps, most of which has been homegrown:

Should the Yankees and Rays pull out all the stops in order to win the division and potentially gain home-field advantage in the ALDS and ALCS?

Over the next four nights, the battle for the American League East will rage in the Bronx, as the Yankees host the Rays for the teams’ final head-to-head confrontations of the regular season. Scant daylight separates the two clubs in the standings, as the Rays enter the (Evil) Empire State trailing the division-leading Bombers by just a half-game, and tied in the loss column. That may sound like a pressure-packed scenario, but at this point in the season, it’s safe to say that each team has become accustomed to hearing the other’s footsteps:

With September approaching, contenders are starting to look at loopholes to help consruct their post-season rosters.

With 30-plus games to play, it might be considered tempting fate for a front office to start planning for the postseason. But seven clubs have improved their odds of making the postseason to 90 percent or better, according to the Playoff Odds Report. And baseball’s calendar demands that GMs and managers begin planning for October now.

Between shifts in team's playoff odds and projected final win totals, who gained (or lost) the most?

In prior years, the various versions of Baseball Prospectus's Playoff Odds Reports were slow to respond to changes in lineups. All of them required the team to start playing differently-sometimes as a result of trades or injuries-before any change would be seen in the playoff odds of the various contenders, and those changes would be pretty seriously depressed by the weight of all the games that had come before.

This year, as a direct result of changes in the way we're running our depth charts, for one of the versions we have done away with any feedback from actual team performance in setting the win percentage that drives the playoff odds program.* The PECOTA-based version of our playoff odds is being entirely set by our projections of player performance. The rates of player performance come from the pre-season PECOTAs, but modified to include some information about how the player has performed so far this year, which Eric Seidman discussed in an Unfiltered post last week. The volume of performance is set by the depth charts, which ultimately means by me, since I've taken the final say on all changes to the depth chart master program. For the PECOTA-based playoff odds, a trade or injury has an immediate impact on the team's expected performance-we can anticipate the change in team performance without waiting for the signal to appear, and its effects on the post-season odds is immediate.

From Carlos Zambrano to Greg Dobbs, the wildly various ramifications of injuries and health issues, as the playoffs get underway.

Team health determines who gets to the postseason as much as talent does. We're looking at eight teams who rank among the best in the business at keeping their players healthy. There are three former Dick Martin winners here (I'm counting Ron Porterfield, who assisted Ken Crenshaw when the Rays won), and teams that have overcome injuries by their successful rehab programs. In the playoffs, injuries are magnified because the compression of talent and time weighs most heavily on any weaknesses a team may have. Most teams come into October healthy, or at the very least, with their health under control. Few have lost major contributors for the season, and in those cases they've all found adequate replacements for that talent. We may not know exactly what s**t works in the playoffs, but I know this much-a focus on health does.

With key players and contending teams straining to reach the finish line and clinch, now's no time to Wrap.

I know that the UTK Wrap confuses some people who don't understand that it's a recap of the week's injuries, so today, I'll confuse you even more. With the regular season heading into its final weekend, there are too many situations where an injury may affect the outcome of a playoff race, how a team preps for the playoffs, or who wins a fantasy league. So today it's not enough to just recap the week that was, and this is a full-on UTK, just like we've had 85 times over the course of this season. Add in 31 UTK Wraps, 30 Team Health Reports, The Mill, and various other pieces, and it's been a full year of work for me. Part of this job is just showing up every day, because if you don't follow the daily patterns and flow of injuries and rehabs, you'll miss something. Thanks to everyone that's made this, the seventh year of UTK, one of the best. Powered by an e-mail that I sent to three friends on an April afternoon in 2002 that gave rise to this column, on to the injuries:

The Cubs and Angels have to worry about their LDS assignments, while the Brewers have to worry about even getting there.

Carlos Zambrano (0 DXL)
If you buy what Bob Brenly said during Friday's game, that Zambrano was losing velocity without having anything physically wrong, then there's still the question of what Zambrano gave up in pursuit of a no-hitter. If you don't buy into Brenly's logic and you worry, like me, that Zambrano's return was just the start of a downward slope that might have been accelerated by 110 pitches at high adrenaline, then you end up at the same place. Zambrano has one start, maybe, before the playoffs, and in that start the Cubs will have to make a lot of decisions. With the division clinched and Zambrano's scheduled Thursday start putting him in position to lead off the Cubs' Division Series, they almost have to see him go the normal distance, hopefully with the same higher elbow at ball release like he had during the no-hitter, before they can write his name into their playoff rotation in ink. If he has another poor performance and looks bad physically, the Cubs do have options, but not nearly as good.

One team has a decided advantage on the injury front heading into the playoffs, while another limps in with a severely depleted squad.

I'll steal from myself for the format of this year's Playoff Health Report. The color designation speaks to how much the player will be affected by his injury, with RED meaning that the player should be considered a non-factor, YELLOW meaning that the injury will affect or limit his play, and GREEN indicating that the player should be able to play through the injury without it having a significant affect on his play.